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From: rpaul@hopi.intel.COM (Richard Paul~)
Newsgroups: comp.lang.perl
Subject: How can I capture STDERR from a command executed externally
Message-ID: <4352@inews.intel.com>
Date: 22 May 91 14:57:31 GMT
Sender: news@inews.intel.com
Reply-To: rpaul@sedona.intel.com
Distribution: usa
Organization: Intel Corporation, ASIC in the Desert
Lines: 42


I want to be able to capture STDERR from an external command and do some 
substitution and reprint it back out.  Following is an experiment I was doing
to get this to work.  The ls command used is the GNU ls, which with the -h
option, prints its options to stderr:

#!/stor/gnu/bin/perl

open(STDERR, ">&STDOUT");
open(STDOUT);
select(STDERR); $| = 1;         # make unbuffered

open(TMP, "ls -h >&STDERR");

while(<STDOUT>)
{
	s/\+/\%/g;
	print $_;
}

close(TMP);
close(STDERR);
close(STDOUT);

The stderr is still going to the tty and not the STDERR filehandle.  Is there
a way to capture the STDERR output of the TMP filehandle.  Any help would be
greatly appreciated.  I am using the following perl:

$RCSfile: perl.c,v $$Revision: 4.0.1.1 $$Date: 91/04/11 17:49:05 $
Patch level: 3

Thanx
-- 
--
___________________________________________________________________________
| Name:  Richard Paul                  | US-Mail: 5000 W. Chandler Blvd.  |
| Dept:  AME Methodology, SQA          | M-stop:  CH3-36                  |
| Group: Arizona Microcomputer Eng.    |          Chandler  AZ, 85226     |
| Tel: 602 554 2793, Fax: 602 554 7281 | E-mail: rpaul@sedona.intel.com   |
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